At allexperts.com I posted a question about Alpha/TV/Orienting:
Kai Schreiber, the expert helping me out here, gave an excellent
an thoughtful answer.
Thank you Kai !
Note, Kai Schreiber has a Graduate Degree in Neuroscience
and a PhD in Physiology.
* * * *
This question is about, what for me at least, is a paradox.
From what I’ve read, people (adults) when they watch TV
their brains produce more Alpha brainwaves, to the point
where Alpha brainwaves dominate. Apparently brainwaves
while watching TV has been extensively studied by
According to this Feb 2002 Scientific American article:
the reason for this brainwave change is the
But from what I’ve read about the Orienting Response,
it actually causes Alpha Brainwaves to be blocked.
So the paradox is, how could the orienting response
cause Alpha waves to be blocked, yet in the case of
TV watching, cause alpha brainwaves to dominate?
I’m no expert on EEG and brain waves. From reading
the article you quote, and related material in
scientific studies and online summaries, I am about
as confused as you are. It seems that TV is associated
both with an increase in alpha activity, suggesting
dreaminess and loss of general focus, and thought to
be capturing attention due to a constant triggering
of the orienting response, which indeed is supposed
to lower alpha activity. Contradictory, it seems.
One possible explanation is that the alpha increase
is relative to other frequency bands and reflects a
shift in what the brain is concerning itself with,
while the momentary decrease in alpha associated
with the orienting response may be an absolute
decrease in energy across bands, indicating a
Technically, an increase in alpha relative to other
frequencies could be occurring at the same time as
an overall decrease, but somehow I doubt that this
is the answer to the riddle.
Sorry I can’t be more helpful on this,
* * * *
Kai’s idea of there being an overall decrease
in brainwave activity makes sense to me.
According to this article from the Journal
“The presence of increased gamma responses for the
voluntary allocation of attention, and its absence
in cases of involuntary capture suggests that the
neural mechanisms governing these two types of
attention are different.”
* * * *
Again, according to that Scientific American
“Alpha waves are blocked for a few seconds before
returning to their baseline level, which is
determined by the general level of mental arousal.
The brain focuses its attention on gathering more
information while the rest of the body quiets.”
“The EEG studies similarly show less mental
stimulation, as measured by alpha brain-wave
production, during [TV] viewing than during
* * * *
The Orienting Response has been extensively studied
and it is clear that it is a natural physiological
reflex that increases alertness.
The difference with regards to TV is that the
Orienting Response is triggered almost continuously
(usually every 3 to 12 seconds). The result
paradoxically is reduced alertness.
As Kai pointed out, perhaps the reason that Alpha
brainwaves dominate during TV viewing is because
maybe other brainwaves such as Beta or Gamma are
also blocked but that they don’t bounce back as
readily as Alpha.
Considering the huge amounts of TV that Americans
watch (especially children) you would think that
this question would have been extensively studied,
with the results widely reported.
Instead, the question of why the Orienting
Response, in the case of TV, has such a
paradoxical effect remains unanswered.
If anyone knows of any relevant research,
please, please post a link or info !
Update, an answer to the paradox: